Difference between revisions of "OpenFOAM/C2/Simulating-flow-in-a-Lid-Driven-Cavity/English-timed"

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|-

|  00:32

|  00:32

|  '''Lid driven cavity''' is the most widely used 2D test  

|  '''Lid driven cavity''' is the most widely used 2D test  

|-

|-

|  case for validation of a '''CFD code'''.

|  case for validation of a '''CFD code'''.

|-

|-

| This is the diagram of '''Lid Driven Cavity''',

| This is the diagram of '''Lid Driven Cavity''',

|-

|-

| the '''boundary conditions''' remain the same.

| the '''boundary conditions''' remain the same.

|-

|-

| A '''moving wall''' and '''three fixedwalls'''.

| A '''moving wall''' and '''three fixedwalls'''.

|-

|-

|  We are solving this for '''Reynolds no (Re) = 100'''.

|  We are solving this for '''Reynolds no (Re) = 100'''.

|-

|-

| The '''moving wall''' has a velocity of 1 meter per second.

| The '''moving wall''' has a velocity of 1 meter per second.

|-

|-

| The '''path''' for the '''Lid Driven Cavity''' is the same as discussed in the installation tutorial.

| The '''path''' for the '''Lid Driven Cavity''' is the same as discussed in the installation tutorial.

|-

|-

|  Now, open a '''command terminal'''.   

|  Now, open a '''command terminal'''.   

|-

|-

| To do this, press '''Ctrl+Alt+t ''' keys simultaneously on your keyboard.

| To do this, press '''Ctrl+Alt+t ''' keys simultaneously on your keyboard.

|-

|-

|-

|-

|and type "run" and press '''Enter'''.

|and type "run" and press '''Enter'''.

|-

|-

|  '''cd (space) tutorials''' and press '''Enter'''.

|  '''cd (space) tutorials''' and press '''Enter'''.

|-

|-

| '''cd '''(space)''' incompressible''' and press '''Enter'''.

| '''cd '''(space)''' incompressible''' and press '''Enter'''.

|-

|-

|'''cd '''(space)''' icoFoam '''(Note that F here is capital) and press '''Enter'''.

|'''cd '''(space)''' icoFoam '''(Note that F here is capital) and press '''Enter'''.

|-

|-

|  '''cd '''(space) '''cavity''' and press '''Enter'''.

|  '''cd '''(space) '''cavity''' and press '''Enter'''.

|-

|-

|Now, type "ls" and press '''Enter'''.

|Now, type "ls" and press '''Enter'''.

|-

|-

|In the file structure of '''cavity''', you will see 3 folders : '''0 , constant , and system'''.

|In the file structure of '''cavity''', you will see 3 folders : '''0 , constant , and system'''.

|-

|-

|  Now, type '''cd''' (space) '''constant''' and press '''Enter'''.

|  Now, type '''cd''' (space) '''constant''' and press '''Enter'''.

|-

|-

| Now type "ls" and press '''Enter'''.

| Now type "ls" and press '''Enter'''.

|-

|-

|  The '''constant''' folder contains another folder named '''polyMesh''' and a file describing the physical properties of fluid.

|  The '''constant''' folder contains another folder named '''polyMesh''' and a file describing the physical properties of fluid.

|-

|-

| Now, type '''cd (space) polymesh''' and Press '''Enter'''.

| Now, type '''cd (space) polymesh''' and Press '''Enter'''.

|-

|-

| '''PolyMesh''' contains a file named 'blockMeshDict'.

| '''PolyMesh''' contains a file named 'blockMeshDict'.

|-

|-

|  Now type "ls" and press '''Enter'''.

|  Now type "ls" and press '''Enter'''.

|-

|-

|  You can see the '''blockMeshDict'''

|  You can see the '''blockMeshDict'''

|-

|-

| To open up the  '''blockMeshDict''' file,  type '''gedit space blockMeshDict'''.

| To open up the  '''blockMeshDict''' file,  type '''gedit space blockMeshDict'''.

(Note that M and D  here are capital).Now press '''Enter'''.

(Note that M and D  here are capital).Now press '''Enter'''.

|-

|-

|  This will Open up the '''blockMeshDict''' file.

|  This will Open up the '''blockMeshDict''' file.

|-

|-

| Let me drag this to the capture area.

| Let me drag this to the capture area.

|-

|-

|  This contains: coordinates for the '''lid driven cavity''',

|  This contains: coordinates for the '''lid driven cavity''',

|-

|-

|'''blocking''' and '''meshing parameters'''

|'''blocking''' and '''meshing parameters'''

|-

|-

|and '''boundary patches.'''

|and '''boundary patches.'''

|-

|-

| Since there are  no '''arcs''' as well as no '''patches''' to be merged, '''edges''' and '''mergePatchPairs''' can be kept empty.

| Since there are  no '''arcs''' as well as no '''patches''' to be merged, '''edges''' and '''mergePatchPairs''' can be kept empty.

|-

|-

| Now close this.

| Now close this.

|-

|-

|  In the command terminal, type : '''cd (space) .. (dot) (dot)'''  and press '''Enter.'''

|  In the command terminal, type : '''cd (space) .. (dot) (dot)'''  and press '''Enter.'''

|-

|-

| Do  this twice. You will come back to the''' cavity''' folder.

| Do  this twice. You will come back to the''' cavity''' folder.

|-

|-

|  Now, type '''cd''' (space) '''system''' and press '''Enter'''.

|  Now, type '''cd''' (space) '''system''' and press '''Enter'''.

|-

|-

|  Now type "ls", press '''Enter'''.  This contains three files-

|  Now type "ls", press '''Enter'''.  This contains three files-

|-

|-

|'''controlDict, fvSchemes''' and '''fvSolutions'''.

|'''controlDict, fvSchemes''' and '''fvSolutions'''.

|-

|-

| '''controlDict''' contains '''control parameters''' for start/end time.

| '''controlDict''' contains '''control parameters''' for start/end time.

|-

|-

|'''fvSolution''' contains '''discritization schemes''' used in '''run time'''.

|'''fvSolution''' contains '''discritization schemes''' used in '''run time'''.

|-

|-

|And, '''fvSchemes''' contains equation for '''solvers''', '''tolerance''' etc.  

|And, '''fvSchemes''' contains equation for '''solvers''', '''tolerance''' etc.  

|-

|-

| Now, again type '''cd (space) (dot dot) .. '''and press '''Enter'''.

| Now, again type '''cd (space) (dot dot) .. '''and press '''Enter'''.

|-

|-

|  Now type '''cd ( space )''' 0 (zero) and Press '''Enter'''.

|  Now type '''cd ( space )''' 0 (zero) and Press '''Enter'''.

|-

|-

| Now type "ls" and press '''Enter'''.

| Now type "ls" and press '''Enter'''.

|-

|-

|  This contains the initial values for '''boundary conditions''' like '''Pressure, Velocity, Temperature''' etc.  

|  This contains the initial values for '''boundary conditions''' like '''Pressure, Velocity, Temperature''' etc.  

|-

|-

| Now type''' cd ( space ) (dot dot) . .''' to return back to the '''cavity''' folder.

| Now type''' cd ( space ) (dot dot) . .''' to return back to the '''cavity''' folder.

|-

|-

|  Now we need to '''mesh '''the geometry.

|  Now we need to '''mesh '''the geometry.

|-

|-

|We are using a coarse mesh here.

|We are using a coarse mesh here.

|-

|-

|  '''Mesh''' the geometry by typing '''blockMesh''' in the '''terminal'''.

|  '''Mesh''' the geometry by typing '''blockMesh''' in the '''terminal'''.

|-

|-

| Now type '''blockMesh '''(Note that M  here is capital) and press '''Enter'''.

| Now type '''blockMesh '''(Note that M  here is capital) and press '''Enter'''.

|-

|-

|  The '''Meshing''' is done.

|  The '''Meshing''' is done.

|-

|-

| If there are some '''errors''' in the '''blockMesh''' file, it will be shown in the '''terminal'''.

| If there are some '''errors''' in the '''blockMesh''' file, it will be shown in the '''terminal'''.

|-

|-

|  To view the geometry,type '''paraFoam'''. Note that 'F' here is capital and press '''Enter'''.

|  To view the geometry,type '''paraFoam'''. Note that 'F' here is capital and press '''Enter'''.

|-

|-

|  This will open the '''paraview window'''.

|  This will open the '''paraview window'''.

|-

|-

|  Now on the left hand side of the '''object inspector''' menu, click on '''Apply.'''

|  Now on the left hand side of the '''object inspector''' menu, click on '''Apply.'''

|-

|-

| You can see the '''lid driven cavity''' geometry. Now close this.

| You can see the '''lid driven cavity''' geometry. Now close this.

|-

|-

|  Check the mesh by typing "checkMesh" in the terminal.

|  Check the mesh by typing "checkMesh" in the terminal.

|-

|-

|Note that 'M' here is capital and press '''Enter'''.

|Note that 'M' here is capital and press '''Enter'''.

|-

|-

| you can see  the number of cells, '''skewness''' and other parameters which are associated with the '''mesh'''.

| you can see  the number of cells, '''skewness''' and other parameters which are associated with the '''mesh'''.

|-

|-

|  Let me switch back to the '''slides'''.

|  Let me switch back to the '''slides'''.

|-

|-

|  The solver we are using here is '''icoFoam''':

|  The solver we are using here is '''icoFoam''':

|-

|-

|  '''icoFoam''' is a '''Transient solver''' for '''incompressible flow''' of '''newtonian fluids'''.

|  '''icoFoam''' is a '''Transient solver''' for '''incompressible flow''' of '''newtonian fluids'''.

|-

|-

|  Let me switch back to the terminal.

|  Let me switch back to the terminal.

|-

|-

|  In the terminal, type "icoFoam".  

|  In the terminal, type "icoFoam".  

|-

|-

|Note that 'F' here is capital and press '''Enter'''.

|Note that 'F' here is capital and press '''Enter'''.

|-

|-

| The  '''Iterations '''running will be seen in the terminal window.

| The  '''Iterations '''running will be seen in the terminal window.

|-

|-

| After the solving is done, type '''paraFoam''' in the terminal to view the geometry and the results.

| After the solving is done, type '''paraFoam''' in the terminal to view the geometry and the results.

|-

|-

|  On the left hand side of '''object inspector''' menu

|  On the left hand side of '''object inspector''' menu

|-

|-

|click on '''Apply'''.Now '''Scroll''' down the properties on '''object inspector''' menu.  

|click on '''Apply'''.Now '''Scroll''' down the properties on '''object inspector''' menu.  

|-

|-

|you can see '''mesh parts, Volume Fields''' etc.

|you can see '''mesh parts, Volume Fields''' etc.

|-

|-

|  Check or uncheck these '''boxes''' in the '''mesh''' part, to view the different boundary regions of '''Lid driven cavity'''.

|  Check or uncheck these '''boxes''' in the '''mesh''' part, to view the different boundary regions of '''Lid driven cavity'''.

|-

|-

| Now, after this, on top of the left-hand side on  '''active variable control ''' drop-down menu, change this from '''solid color''' to '''p''' or capital '''U''' which are the '''initial conditions''' such as '''pressure, velocity'''.

| Now, after this, on top of the left-hand side on  '''active variable control ''' drop-down menu, change this from '''solid color''' to '''p''' or capital '''U''' which are the '''initial conditions''' such as '''pressure, velocity'''.

|-

|-

|I will select capital 'U'. Now this will show you the initial condition of velocity.  

|I will select capital 'U'. Now this will show you the initial condition of velocity.  

|-

|-

|  On top of the''' paraview''' window, you will see the''' VCR control'''.

|  On top of the''' paraview''' window, you will see the''' VCR control'''.

|-

|-

|Click on the '''play''' button.

|Click on the '''play''' button.

|-

|-

|  Now this is the final result of '''velocity''' for the '''lid driven cavity'''.

|  Now this is the final result of '''velocity''' for the '''lid driven cavity'''.

|-

|-

| Toggle on the '''color legend''' by clicking on  the top left of the '''active variable control''' menu.

| Toggle on the '''color legend''' by clicking on  the top left of the '''active variable control''' menu.

|-

|-

| This is the''' color legend''' for '''U velocity'''.

| This is the''' color legend''' for '''U velocity'''.

|-

|-

| We need to validate the results obtained.

| We need to validate the results obtained.

|-

|-

|To do this, let us plot the '''U''' and '''V velocity'''.

|To do this, let us plot the '''U''' and '''V velocity'''.

   

   

|-

|-

| To do this, go to '''Filters''' scroll down > '''Data Analysis''' > '''Plot Over line'''.

| To do this, go to '''Filters''' scroll down > '''Data Analysis''' > '''Plot Over line'''.

|-

|-

| Click on it.

| Click on it.

|-

|-

|  You can see  X , Y and Z axes.

|  You can see  X , Y and Z axes.

|-

|-

|  Select the '''X & Y axis''' turn by turn.

|  Select the '''X & Y axis''' turn by turn.

|-

|-

|I will select the '''X axis''' and click '''Apply'''.

|I will select the '''X axis''' and click '''Apply'''.

|-

|-

|  You can see '''Pressure''' and '''velocity''' '''plots''' being plotted.

|  You can see '''Pressure''' and '''velocity''' '''plots''' being plotted.

|-

|-

|  Since it is a non dimensional analysis, we need to plot the graph for '''u/U v/s y/L''' for '''Reynolds number =100'''

|  Since it is a non dimensional analysis, we need to plot the graph for '''u/U v/s y/L''' for '''Reynolds number =100'''

|-

|-

|  To do this, in '''Plot Data''' click on the '''Y-axis'''

|  To do this, in '''Plot Data''' click on the '''Y-axis'''

|-

|-

|and click '''APPLY'''.

|and click '''APPLY'''.

|-

|-

|  You can see the''' plot'''.

|  You can see the''' plot'''.

|-

|-

|Now in menu bar, go to '''File > Save Data'''.

|Now in menu bar, go to '''File > Save Data'''.

|-

|-

| Give  appropriate name to your file.

| Give  appropriate name to your file.

|-

|-

|  I will give this as "cavity".

|  I will give this as "cavity".

|-

|-

|The file will be saved as ".csv" (dot csv) file.

|The file will be saved as ".csv" (dot csv) file.

|-

|-

| Now click OK. Again click OK.

| Now click OK. Again click OK.

|-

|-

|  Now go to the '''cavity''' folder of '''openfoam directory'''.

|  Now go to the '''cavity''' folder of '''openfoam directory'''.

|-

|-

|Scroll down. you can see the '''cavity.csv''' file.

|Scroll down. you can see the '''cavity.csv''' file.

|-

|-

| Open it in '''Open office''' or '''LibreOffice Spreadsheet'''.

| Open it in '''Open office''' or '''LibreOffice Spreadsheet'''.

|-

|-

| In the LibreOffice spreadsheet, copy the U0 (u velocity) and to the right points 1(Y-axis) columns in another spreadsheet.  

| In the LibreOffice spreadsheet, copy the U0 (u velocity) and to the right points 1(Y-axis) columns in another spreadsheet.  

|-

|-

|  Now, divide both these columns, that is, '''u zero''' by capital U and '''points 1''' by capital L

|  Now, divide both these columns, that is, '''u zero''' by capital U and '''points 1''' by capital L

|-

|-

| and plot the results in '''libreoffice''' charts option on top, in the menu bar.

| and plot the results in '''libreoffice''' charts option on top, in the menu bar.

|-

|-

| Now let me switch back to the slides.

| Now let me switch back to the slides.

|-

|-

| Results obtained will be similar to this figure.

| Results obtained will be similar to this figure.

|-

|-

| '''Validate''' the results on a  paper published on '''Lid Driven Cavity by : Ghia et al. (1982''') and Results obtained from Fluent.

| '''Validate''' the results on a  paper published on '''Lid Driven Cavity by : Ghia et al. (1982''') and Results obtained from Fluent.

|-

|-

|  In this tutorial, we learnt:   

|  In this tutorial, we learnt:   

|-

|-

| File structure of '''Lid Driven cavity'''

| File structure of '''Lid Driven cavity'''

|-

|-

| '''Solved lid driven cavity'''.

| '''Solved lid driven cavity'''.

|-

|-

|'''Post-processing of solutions'''

|'''Post-processing of solutions'''

|-

|-

|And '''Validation'''.

|And '''Validation'''.

|-

|-

|  As an assignment, Change some parameters in the '''lid driven cavity'''.

|  As an assignment, Change some parameters in the '''lid driven cavity'''.

|-

|-

|'''Velocity Magnitude''' in the '''0 folder'''.

|'''Velocity Magnitude''' in the '''0 folder'''.

|-

|-

| '''Kinematic viscosity'''  in '''transport Properties''' in '''constant''' folder.

| '''Kinematic viscosity'''  in '''transport Properties''' in '''constant''' folder.

|-

|-

|And, plot results of '''u/U and y/L'''.

|And, plot results of '''u/U and y/L'''.

|-

|-

| Watch the  video available at this URL: http://spoken-tutorial.org/What_is_a_Spoken_Tutorial  

| Watch the  video available at this URL: http://spoken-tutorial.org/What_is_a_Spoken_Tutorial  

|-

|-

|It summarizes the '''Spoken Tutorial''' project.  

|It summarizes the '''Spoken Tutorial''' project.  

|-

|-

|If you do not have good bandwidth, you can download and watch it.

|If you do not have good bandwidth, you can download and watch it.

|-

|-

|  The Spoken Tutorial project team:

|  The Spoken Tutorial project team:

|-

|-

|Conducts workshops using spoken tutorials

|Conducts workshops using spoken tutorials

|-

|-

|Gives certificates to those who pass an online test.

|Gives certificates to those who pass an online test.

|-

|-

|For more details, please write to us at:contact@spoken-tutorial.org

|For more details, please write to us at:contact@spoken-tutorial.org

|-

|-

| '''Spoken Tutorials''' are part of '''Talk to a Teacher''' project.  

| '''Spoken Tutorials''' are part of '''Talk to a Teacher''' project.  

|-

|-

|It is supported by the National Mission on Education through ICT, MHRD, Government of India.  

|It is supported by the National Mission on Education through ICT, MHRD, Government of India.  

|-

|-

|More information on the same is available at the following URL:  http://spoken-tutorial.org/NMEICT-Intro

|More information on the same is available at the following URL:  http://spoken-tutorial.org/NMEICT-Intro

|-

|-

|  This is Rahul Joshi from IIT Bombay, signing off.

|  This is Rahul Joshi from IIT Bombay, signing off.

|-

|-

|Thanks for joining.

|Thanks for joining.

|}

|}